Much of the population has experienced a skin condition such as a rash, a pressure ulcer, a wound such as a cut or first degree burn, an allergic reaction, or any other skin condition that can cause itching, inflammation, pain, or any other type of discomfort that has required topical application of a cream or ointment to assist in the healing process. Often, some of these conditions are more prevalent in infants, the elderly, and infirm. For instance, infants, the elderly, and infirm can be susceptible to developing incontinent dermatitis, which occurs when the skin is exposed to prolonged wetness, increased skin pH caused due to contact with urine and feces, and the resulting breakdown of the stratum corneum, or the outermost layer of the skin. Meanwhile, pressure ulcers, also known as decubitus ulcers or bedsores, are also a concern. Pressure ulcers are localized injuries to the skin and/or underlying tissue that usually occur over a bony prominence as a result of pressure, or pressure in combination with shear and/or friction. The most common sites are the sacrum, coccyx, heels or the hips, but other sites such as the elbows, knees, ankles or the back of the cranium can be affected. Pressure ulcers occur due to pressure applied to soft tissue resulting in completely or partially obstructed blood flow to the soft tissue. Factors that can contribute to the formation of ulcers include protein-calorie malnutrition, microclimate (skin wetness caused by sweating or incontinence), diseases that reduce blood flow to the skin, such as arteriosclerosis, or diseases that reduce the sensation in the skin, such as paralysis or neuropathy.
The aforementioned conditions, and other skin conditions, can be prevented or treated, for instance, by the application of an active agent to the affected area of the skin. Active agents can, for instance, help speed up the wound healing process and can also limit the skin's exposure to excessive moisture. As such, one approach for treating these skin conditions is to block moisture from reaching the skin, such as by the application of oil-based protectants or barrier creams, such as various over-the-counter creams or ointments containing moisture barrier active agent particles, to the affected area. However, if the skin is not thoroughly dry, some of these oil-based protectants and creams can actually seal the moisture inside the skin rather than outside the skin. Further, such protectants and creams are very viscous and can be greasy, resulting in difficulty in removing the protectants and creams from one's hands after application onto the affected area of the skin. In addition, rubbing these products into the skin can cause additional discomfort or pain, and in the event that a caretaker or healthcare provider must apply the product to a patient, this could lead to embarrassment for both the patient and caretaker depending on the location of application.
As such, a need exists for a composition that can provide an even coating of an active agent to the skin that is easier to apply and that does not cause discomfort. One approach is to use an active agent in conjunction with a propellant to create a sprayable composition. However, often the high viscosity of the resulting aerosol spray composition means that it can be difficult to formulate the composition into a medium that can be sprayed due to issues with clogging of active agent particles in the valves and nozzle in the dispenser. Meanwhile, to counteract this problem, other sprayable compositions are formulated to have a low viscosity to allow for spraying, but this can result in compositions that are not viscous enough when applied to the skin's surface, resulting in a runny product that does not evenly coat or effectively contact the skin.
Still another problem associated with the aforementioned sprays is that the active agents of the sprayable compositions are particulate-based and often settle to the bottom of the container in which the e composition is stored, particularly when the viscosity is low, resulting in caking of the active agent in the container and the inability to deliver the active agent in a uniform manner.
As such, a need exists for a stable, sprayable composition containing active agent particles that remain substantially homogeneously distributed and that can be evenly sprayed onto the skin as a fine mist without clogging.